Conformable oil filtering device



March 5, 1968 F. ROBERT J. FOWLER CONFORMABLE OIL FILTERING DEVICE Filed May 12, 1966 2 Sheets-Sheet 1 INVENTOR.

March 1968 F. ROBERT J. FOWLER 3,

CONFORMABLE OIL FILTERING DEVICE 2 SheetsSheet 2 Filed May 12, 1966 ll-lll INVENTOR. ZEoberf Jfiwler United States Patent O 3,371,793 CONFORMABLE OIL FILTERING DEVICE F. Robert J. Fowler, Flint, Mich., assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed May 12, 1966, Ser. No. 549,674 1 Claim. (Cl. 210445) ABSTRACT OF THE DISCLOSURE A filter device comprising an envelope of porous filter material sandwiched between impervious sheet material, two ports or ducts being provided with one of those ports or ducts extending through the impervious material and the filter material to the interior of the envelope and the other of those ports or ducts extending through the impervious material. Preferably, the filter material is in one piece and in the form of a folded sheet so that one edge of the envelope formed is a fold and the remainder of the envelope perimeter is clamped or sealed by clamping pressure of the impervious sheet material enclosing the envelope. The concept is such that the device is conformable to a wall defining a restricted zone of use such as a transmission housing or an engine crankcase and despite irregularities and shallow areas which may characterize such zone.

STATE OF THE PRIOR ART A satisfactory oil filtering device for use in an automobile crankcase is disclosed in the US. Patent to Paul D. Blystone No. 3,121,473. This patented device does not conform with the wall of a housing as closely as is desirable and often necessary in the interest of compactness.

DESCRIPTION OF THE INVENTION In the drawings:

FIGURE 1 is a side elevation of a transmission casing of the type utilized in automotive vehicles, a portion being broken away to show the installation of a filter device constituting one embodiment of the present invention;

FIGURE 2 is an enlarged top view of the filter device as seen looking in the direction of the arrows 22 in FIGURE 1;

FIGURE 3 is a sectional view taken along the line 3-3 of FIGURE 2 and drawn to a slightly smaller scale;

FIGURE 4 is a sectional view looking in the direction of the arrows 4-4 in FIGURE 2;

FIGURE 5 is a sectional view with parts broken away looking upward, i.e., in the direction of the arrows 55 in FIGURE 4; and

FIGURE 6 is a perspective view of an envelope utilized in the filter device of FIGURES 1 to 5, a portion of the sheet material of the envelope as positioned prior to fold- .ing being illustrated in clot and dash lines.

In FIGURE 1, a transmission housing 10 is shown to illustrate one use to which the filter device 12 of the present invention could be put. The device 12 could be utilized in the crankcase housing of an engine or in some other housing in which available space is at a premium. In the drawing, however, the housing 10 is provided with a cover 14 enclosing an opening 16 in the housing and having a flat bottom 18. The specific filter device 12 illustrated is designed closely to follow the bottom wall 18 which, of course, may be termed a wall of the housing 10.

The device 12 comprises a top sheet 20 and a bottom sheet 22 each of which is of impermeable sheet metal and preferably of corrugated form. The top sheet 20 bears 3,371,793 Patented Mar. 5, 1968 corrugations 24 (FIGURES 2 and 4) which extend toward a depression 26 (FIGURE 3) which in turn leads to a neck 28. The top sheet 20 is apertured as at 30 tightly to receive one end of a duct 32. The latter may be omitted if desired. The perimeter or margin of the plate or sheet 20 is doubled upon itself as at 34 thereby providing a means for holding facing surfaces of the sheets 20 and 22 in sealed relation and the sheets 20 and 22 are so formed as to define a chamber 36 between them. This'chamber extends substantially the full area of each of the sheets 20 and 22. The margin 40 of the sheet 20 around the duct 32 is bent around tightly to retain a porous sheet of filter material 50.

This material 50 may be of paper or any foraminous material such as a screen or cloth but it is preferably fiberous and necessarily of such porosity as to be suitable for the particular use to which the filter device is to be put. The filter material 50 is preferably in one piece and is provided in flat form as depicted in FIGURE 6 with the aperture 52 therein. This aperture is of a size subsequently to fit the duct 32. Before placing the filter material 50 in the sandwich arrangement of the filter device assembly, the material 50 is folded as illustrated in FIGURE 6. The folded sheet is placed between the two sheets 20 and 22 in such a way that the folded edge 54 traverses that portion of the chamber 36 which lies beneath the depression 26. The remainder of the perimeter of the folded sheet 50 is clamped together by the crimped margin 34 to form asealed envelope.

In the use of the device, oil from the transmission is forced downwardly through the duct 32 and into the envelope made up of the filter material 50. Any dirt entrained in that oil is trapped within the envelope and the cleansed oil passes through the filter material 50 and then along the passages formed between the envelope and the sheets 20 and 22 to the depression 26, then out from the filter device 12 by way of the discharge tube 28.

The envelope and in fact the entire filter device 12 is generally flat in configuration and, therefore, lends itself very well in being conformable to the wall of a housing even though the space available is extremely restricted. FIGURE 2 shows a number of areas 60, 62, 64, 66, 68, and 70 which are not corrugated. These are areas which are depressed below the aspices of the corrugations 24 because of portions of the transmission which extend downwardly and in close proximity to the wall 18. This demonstrates how the filter device 12 may be adapted for a given use despite certain otherwise interfering obstacles. The contour of the perimeter of the device may be varied without departing from the principles of the invention and the same is true with the cross sectional contour or shape of the filter device. Preferably, the filter material 50 is made with a roughened surface to promote fluid flow not only within the envelope but also along the exterior surfaces thereof. It is also preferable and as illustrated in the drawings to have the sheets 20 and 22 corrugated to enhance the flow although roughness of the material 50 may alone be relied upon in this regard. The inlet duct 32 obviously forms no part of the invention and may be made very short or omitted dependent upon the specific use of the filtering device.

I claim:

1. A filter device for conforming with a wall, said device being generally fiat and comprising an envelope of porous sheet material, impervious sheet material having facing margins joined to form a chamber, liquid discharge means formed in said impervious sheet material, said envelope being folded upon itself and a portion of its perimeter as folded presenting a fold adjacent to said liquid discharge means, the remainder of the perimeter of said folded envelope being retained between said facing margins to close said envelope, inlet means for conducting liquid through said impervious sheet material and one wall of said envelope to the interior of the latter, contacting facing portions of said porous sheet material defining inlet passages leading from said inlet means, and contacting facing portions of aid porous sheet material and said impervious sheet material defining outlet passages leading to said liquid discharge means, the inside surfaces of said impervious sheet material being corrugated partially to determine said outlet passages, and said contacting facing portions of said porous sheet material being roughened to References Cited UNITED STATES PATENTS 1/1931 Wiltse 2l0168 11/1965 Berg 2lO-448 0 SAMIH N. ZAHARNA, Primary Examiner.

FMNK MEDLEY, Examiner. 

